Strapping head assembly for a wrapping machine

Abstract

A strapping head assembly has a central axle, a braking tube, a lower securing plate, a braking pad, an adjusting base, a biasing member, an adjusting nut, a strap-holding collar and an upper holding base. The braking tube is mounted rotatably around the central axle. The lower securing plate is mounted on the bottom of the braking tube. The braking pad is attached to the top of the braking tube. The adjusting base is adjustably mounted on the central axle and abuts with the braking pad. The biasing member is mounted around the central axle and abuts against the adjusting base. The adjusting nut is screwed with the central axle and abuts with the biasing member. The strap-holding collar is mounted around the central axle. The upper holding base is mounted around the central axle and has an abutting flange mounted over the strap-holding collar.

1. A strapping head assembly for a wrapping machine comprising:
 a central axle having a top, a bottom and a thread formed on the top; 
 a braking tube mounted rotatably around the central axle and having a top and a bottom; 
 a lower securing plate mounted on the bottom of the braking tube; 
 a braking pad attached to the top of the braking tube and having a top; 
 an adjusting base adjustably mounted on the central axle and having a top and a bottom abutting with the top of the braking pad; 
 a biasing member mounted around the top of the central axle and having a top and a bottom abutting against the top of the adjusting base to provide a biasing force to the adjusting base; 
 an adjusting nut screwed with the thread on the top of the central axle and abutting with the top of the biasing member; 
 a strap-holding collar mounted around the top of the central axle; and 
 an upper holding base mounted around the top of the central axle and having an abutting flange formed around and protruding from the upper holding base and mounted over the strap-holding collar. 
 
   
   
     2. The strapping head assembly as claimed in  claim 1 , wherein the central axle further has an engaging block formed on and axially protruding from the bottom of the central axle. 
   
   
     3. The strapping head assembly as claimed in  claim 2 , wherein the lower securing plate has multiple securing members mounted on the lower securing plate for inserting into and holding a bottom of a strap reel. 
   
   
     4. The strapping head assembly as claimed in  claim 3  further comprising a bushing mounted around the bottom of the central axle between the central axle and the lower securing plate and having an annular lip formed around and protruding from the bushing. 
   
   
     5. The strapping head assembly as claimed in  claim 4 , wherein the adjusting base further has a holding tube formed on and protruding from the top of the adjusting base and holding the biasing member inside;
 the strap-holding collar is mounted around the holding tube; 
 the upper holding base is mounted around the holding tube between the holding tube and the strap-holding collar. 
 
   
   
     6. The strapping head assembly as claimed in  claim 5  further comprising a bearing mounted between the upper holding base and the strap-holding collar. 
   
   
     7. The strapping head assembly as claimed in  claim 6 , wherein the upper holding base further has a threaded hole radially defined in the upper holding base; and
 a limiting bolt is screwed into the threaded hole in the upper holding base and has an end abutting against the holding tube on the adjusting base. 
 
   
   
     8. The strapping head assembly as claimed in  claim 7 , wherein the braking tube further has two bearings mounted around the central axle respectively at the top and bottom of the braking tube. 
   
   
     9. The strapping head assembly as claimed in  claim 1 , wherein the lower securing plate has multiple securing members mounted on the lower securing plate for inserting into and holding a bottom of a strap reel. 
   
   
     10. The strapping head assembly as claimed in  claim 9  further comprising a bushing mounted around the bottom of the central axle between the central axle and the lower securing plate and having an annular lip formed around and protruding from the bushing. 
   
   
     11. The strapping head assembly as claimed in  claim 10 , wherein the adjusting base further has holding tube formed on and protruding from the top of the adjusting base and holding the biasing member inside;
 the strap-holding collar is mounted around the holding tube; 
 the upper holding base is mounted around the holding tube between the holding tube and the strap-holding collar. 
 
   
   
     12. The strapping head assembly as claimed in  claim 11  further comprising a bearing mounted between the upper holding base and the strap-holding collar. 
   
   
     13. The strapping head assembly as claimed in  claim 12 , wherein the upper holding base further has a threaded hole radially defined in the upper holding base; and
 a limiting bolt is screwed into the threaded hole in the upper holding base and has an end abutting against the holding tube on the adjusting base. 
 
   
   
     14. The strapping head assembly as claimed in  claim 13 , wherein the braking tube further has two bearings mounted around the central axle respectively at the top and bottom of the braking tube. 
   
   
     15. The strapping head assembly as claimed in  claim 1  further comprising a bushing mounted around the bottom of the central axle between the central axle and the lower securing plate and having an annular lip formed around and protruding from the bushing. 
   
   
     16. The strapping head assembly as claimed in  claim 1 , wherein the adjusting base further has holding tube formed on and protruding from the top of the adjusting base and holding the biasing member inside;
 the strap-holding collar is mounted around the holding tube; 
 the upper holding base is mounted around the holding tube between the holding tube and the strap-holding collar. 
 
   
   
     17. The strapping head assembly as claimed in  claim 16 , wherein the upper holding base further has a threaded hole radially defined in the upper holding base; and
 a limiting bolt is screwed into the threaded hole in the upper holding base and has an end abutting against the holding tube on the adjusting base. 
 
   
   
     18. The strapping head assembly as claimed in  claim 1  further comprising a bearing mounted between the upper holding base and the strap-holding collar. 
   
   
     19. The strapping head assembly as claimed in  claim 1 , wherein the braking tube further has two bearings mounted around the central axle respectively at the top and bottom of the braking tube. 
   
   
     20. The strapping head assembly as claimed in  claim 1 , wherein the upper holding base further has a threaded hole radially defined in the upper holding base; and
 a limiting bolt is screwed into the threaded hole in the upper holding base and has an end abutting against the adjusting base.